Today we carried on with our machines week and investigated screws. Once again we started off by reading a book. This "Machines Inside Machines" series is really good with facts, photos and experiments to do.
The book gave us this idea for making a screw using a triangle of paper; it shows how the ramp winds around to form the thread.
I had collected lots of things from around the house that featured screws. The children spent a while playing with and investigating them to see how they worked. We also looked at drills to see how they compare to screws.
Next the children sorted our objects into 2 groups. Those with coarse threads and those with fine threads. We did some screwing into wood to find out how the thread coarseness affects the performance of the screw. Fine threads are easier to screw in but take longer.
We had talked about Archimedes screws for lifting things and conveyor screws for moving loads along. We made this Archimedes screw (below and top of page) with a Pringle box and plastic piping (from Bunnings in the hose pipe section). Later we had more fun with it in the bath.
To finish off we investigated how nuts and bolts hold things together. The children used their Mechano kits to make these models.
Tomorrow we will be investigating wheels, pulleys and cams. Visit soon!